Abstract
At the cellular level, some patterns of excitation of neurons have been found to induce long-term increases in synaptic strength between neurons, tlu·ough a process termed long-tem1 potentiation (L TP). While the mechanism of LTP induction is well understood, the mechanisms that lead to the maintenance of synaptic strengthening are not as well understood. PKM( is an isoform of the PKC superfamily and is claimed to be necessary for late-phase LTP maintenance. The main evidence for the role of PKM1; was inferred from reports that L TP can be reduced by the myristoylated 1; -pseudosubstrate peptide (ZTP), claimed to inhibit PKq spccii1cally. Our objectives in this study were to produce stable L TP recordings for up to three hours after induction in an open chamber. This allowed us to test whether we could reproduce ZIP-induced L TP reversal. Measurements were made in the rat CA I region of the hippocampus, as measured by Held recordings. Our experiments have shown that we have successfully induced late phase long-term potentiation in the stratum radiatum of the. CA I region in the hippocampus. However, we were not been able to produce L TP reversal by adding ZIP one hour after LTP induction. We can therefore conclude that furth!!r research should focus on ZIP specificity and the reproducibility of ZIP induced L TP reversal.